Gas burners



R. BUNS GAS BURNERS Jan. 3l, 1967 4 Sheets-Sheet 1 Filed Feb. ll, 1965 wilg;

Jan. 31, 1967 R, BUNS 3,301,312

GAS BURNERS Filed Feb. 1l, 1965 4 Sheets-Sheet 2 Fig. 5 F195 Jan. 3l, 1967 R. BUNS 7 3,301,312

GAS BURNERS Filed Feb. ll, 1965 4 Sheets-Sheet 3 fnmmmummwmmw/ Fig 70 Fig. 71

Jan. 31, 1967 R. BLJNs 3,301,312

GAS BURNERS Filed Feb. ll, 1965 4 Sheets-Sheet 4 United States Patent O 3,301,312 GAS BURNERS Rolf Buns, Blucherstrasse 9, Hamburg-Altona, Germany Filed Feb. 11, 1965, Ser. No. 431,917 Claims priority, application Germany, Feb. 13, 1964, E 75,409 9 Claims. (Cl. 158-116) This invention relates to a secondary nozzle plate for Bunsen type gas burners with individually projecting nipples or jets, particularly for gas heating furnaces or ovens and the like.

Bunsen type burners operate with natural air feed. The flow of combustion gas emerging from a primary nozzle and directed into a mixing tube entrains primary air and mixes with this in the mixing tube and the following distribution chamber, if there is one. From the distribution chamber the gas mixture emerges through one or more secondary nozzles into the combustion chamber. At this point the gas is ignited. Secondary air is sucked from the vicinity of the nozzle and the flame.

In order to facilitate the feed of secondary air larger size burners are formed as nipple type burners. Here, a multiplicity of nipple-like projecting individual nozzles are provided on a secondary nozzle plate. Because of the spacing of these individual nozzles the secondary air can arrive unhindered at each individual burner nozzle, all the more easily the higher the individual nozzles or nipples are. The after-burning is thereby improved and a multiplicity of low flames are obtained instead of one high ame.

Nozzle plates for such nipple burners have long been produced practically only from cast material, since in producing from sheet material it was not possible to draw nipples of sucient height, for instance lO mm. apart and 10 to 20 mm. high. The cast nozzle plates have not only the disadvantage that they are expensive because of the way in which they are produced, but they are also generally inaccurate and because of their roughness are unfavourable for the gas and air ow.

The primary object of the present invention is to produce nozzle plates with very high burner nipples or jets formed as desired, in a relatively simple manner and thereby to avoid the abovementioned disadvantages of the long known types. This is obtained by assembling them from individual elements complementing one another, and form the nozzle nipples or jets by their sides or rims standing up in each case from a base part and forming between them individual nozzles having an outflow crosssection.

The nozzle plates are therefore formed from individual elements which can be produced very easily per se and, in accordance with the invention, can be in particular bent and pressed out of sheet material. The nozzle apertures are formed between the individual elements, that is to say between their upstanding sides or rims. Each individual element consists practically only of a base part and its bent-up sides or rims. It is clear that the height of these rims and hence the nipple or jet height of the burner produced is not critical from the production viewpoint. The elements can be produced with greater accuracy, that is to say, with nozzle forms which could never have been produced in the case of nozzle plates drawn altogether from sheet material or only with diiculty in the case of nozzle plates cast altogether.

The feed of secondary air no longer encounters any diiculties with the construction of the nozzle plate in accordance with the invention. The flames are short with reduced after-burning. The combustion chambers can be kept small. The formation of CO is not to be feared.

l It is particularly advantageous if the nozzles are formed as slot nozzles. However, they can also easily be formed 3,3L3-l2 Patented Jan. 3l, 1967 ICC as circular nozzles, for example again as a row of spaced.

circular nozzles along the boundary line between each two elements. In this connection, the elements themselves may be of any complementary form, for instance, equilateral triangles with nozzles at each of the three sides. The construction of a nozzle plate with elements which are rectangular and have sides or rims forming nozzles at two opposite faces, while the two other faces are formed as gripping surfaces, these elements being gripped together in a row, is however particularly simple. The slot nozzles or rows of smaller nozzles are placed transversely to the direction of the row arrangement.

In this connection, in accordance with a further feature of the invention, the gripping surfaces of the elements can be extended so that they project laterally beyond the areas or zone of the actual nozzle plate and thus screen the secondary nozzles from the primary nozzles or from the sides of the distribution chamber. In this connection they should be particularly bent obliquely to the bottom part of the elements. This makes it diicult for the ame to strike over to the primary nozzle.

It is particularly advantageous if the discharge crosssections of the nozzles are Wider than their inlet crosssections. Having gases with a low ignition velocity and a high proportion of incombustible gases-such as for instance COZ-it easily happens that the flame core does not adhere to the secondary nozzle but breaks off. In order to prevent this, the discharge velocity of the gas mixture at the secondary nozzle must be reduced. Difficulties easily arise particularly in connection with variations in quality of the gas. In operating gas heating furnaces not having a chimney, in which the fresh air is sucked in through a pipe lying in the waste gas pipe and which is therefore preheated during the operation of the heating furnace, a further difficulty arises for the following reasons. It is precisely gases with a relatively high proportion of incombustible gases which require a high admixture of primary air in order to reach the desired combustion result. With the said types of furnace the fresh air at the beginning of operations is fed in at a temperature of for instance 20 C., while the temperature of operation however with such a furnace is from about 70 to C. The result of this is a very considerable variation in the combustion properties of the gas mixture. It is, therefore, practically impossible to obtain a correct mixture velocity at the secondary nozzles underall circumstances and for all possible kinds of gas occurring. This disadvantage is avoided by the nozzle form indicated, which can be particularly simply produced with the nozzle plates assembled from individual elements in accordance with the invention.

In accordance with a further feature of the invention, the widening of the cross-section the nozzle at the discharge or outlet end can be a multiple of the cross-section at the entry end. The widening of the discharge cross-section results in a substantially proportional reduction of the flow velocity inside the nipple. This prevents any breaking off of the llame.

The individual elements can be sealed in respect of one another simply by the elements lbeing machined with higher accuracy and being tightly gripped together. This also app-lies in particular to the lateral ends of the nozzles, which for this purpose advantageously lie in the boundary plane of the elements.

The invention will Vbe described -in more detail by way of example with reference to the accompanying drawings in which:

FIG. l is a plan view of one form of nozzle element formed lin accordance with the present invention;

IF-IG. 2 is a side elevational view of the nozzle element of FIG. l;

FIG. 3 is a transverse vertical cross-sectional View of the nozzle element of FIG. l;

lFIG. 4 is a transverse vertical cross-sectional View of the composite nozzle plate assem-bly formed from the nozzle elements of FIGS. 1-3;

FIGS. 5 through 9 are perspective views of nozzle plate assemblies, formed in accordance with the Ipresent inven- Vtion and depicting various modifications of the basic concept;

FIG. is a side elevational view of a burner, in which the nozzle plate assembly of the present invention is inconporated;

IFI-G. 11 is an end elevational View of the "burner of F'IG. 10;

FIG. 12 is a longitudinal sectional view of the burner of FIG. 110, and

FIG. 13 is a fragmentary perspective view of a modified burner which incorporates the nozzle plate assembly of the present invention.

Referring to the drawings, each element 1 consists of a base part 2 and two sides or rims 3 bent vup opposite one another. The end portions 4 of these sides or rims 3 lie in substantially the same plane and are disposed in the dividing Iplane 5 of the adjacent elements. 'Ihe areas or portions 6 which are between the end portions 4 are set inwardly or indented from the end .portions 4 and are spaced back from the dividing plane so that in this area or zone a slot 7 is produced between the sides or rims of -two adjacent elements. rI`:he `co-operating sides or rims 3 form a nozzle or nipple 8, which in the example shown has a slot form.

The base part 2 of each element is extended at its opposite ends beyond the sides or areas to provide gripping surfaces 9, by means of which a linear series of adjacent elements can be gripped together to form a nozzle plate, a holding fillet 10 for instance gripping over these gripping surfaces over the whole length of the elements. The nozzles can, of course, also be fixed individually at these plates to the edges of the distribution chamber 11.

The nozzle slots widen from an inlet cross-section 12 to their outlet cross-section 13.

FIGURES 5 to 9 show various nozzle plates formed from nozzle elements which are formed in accordance with the present invention. A suitable form may be selected according to the particular purpose of application. The embodiment shown in FIGURE 5 corresponds to that shown in FIGURES 1 to 4, in that it is a slot nozzle. -In FIGURE 6, two slot nozzles lie in each case adjacent to one another in their longitudinal direction and in the direction transverse to .the longitudinal direction of the burner.

The embodiment shown in FIGURE 7 substantially corresponds to that shown in FIGURE `6', except that the individual nozzle elements are connected together by wires or thin rods 20. These rods pass through the bentup nozzle rims :3 in the central zone of a nozzle slot. Their primary object is to simplify the fitting of burner plates, the individual elements being already held together in the desired number before final fitting. Secondly, an additional turbulence of the outflowing Igas is obtained in this way and consequently a speedier and more complete 'combustion is obtained and the danger of the flame breaking olf is reduced.

FIGURE' 8 shows nozzle elements which form together in each case rows of nozzles in fours, the length of which substantially corresponds to their width.

Rows of four are also formed by the nozzle elements shown in FIGURE 9. Here the nozzle apertures are oval or round.

The burner consists of a distribution chamber 11 with a nozzle plate applied thereon, a mixing tube 14 projecting into the distribution chamber, a primary nozzle (not shown), which is directed into the mix-ing tube and is mounted in the aperture 15 of the fixing angle 16. In order to prevent a striking-over of the flame from the 4 secondary nozzle 8 to the primary nozzle, in the embodiment shown in FIGURES 10 to 12 both the fixing angle 16 and `the nozzle element 1 are fitted with screening surfaces 17 or 18 which are slightly inclined from the plane of the base parts 2 of the elements.

FIGURE 13 shows such a burner in perspective in a somewhat varied form. Here, the nozzle elements of FIGURE 7 are used. The individual nozzle elements are held Iby the gripping end portions 9 of their base parts in lateral folds 21. They are :held fast therein in such a way that normally yadditional holding means are unnecessary. In the longitudinal direction they are irst secured by the Wires 20 which are bent round at the ends 22. The base parts 2 of the last elements 23 in each case of a row of nozzle elements can also be spot-welded at their corners 24 to lthe folds.

In this embodiment, no screening surfaces corresponding to those designated by reference numerals 17 and 18 in FIGURES 10` to 12 are present. Any striking-over of the fiame to t-he primary nozzle held in the aperture 1S is prevented by the side surfaces 25 of the corresponding housing part.

The bur-ner element, in accordance with the invention, is also suitable for very small nipple dimensions and spacin-gs, down to spacings of 2 mm., with any desired height ofthe nipples.

It will be 'obvious that, although specific embodiments `of the invention have been described herein, in detail, many modifications can be made therein without thereby departing from the scope of the invention as defined in the appended claims.

I claim:

1. In a gas burner comprising an elongated casing having a longitudinal primary distribution chamber, said casing havin-g a longitudinal opening in said chamber; a nozzle plate assembly structurally engaging the opening in the cas-ing and comprising a row of individual nozzles separately upstanding zfrom the casing, said nozzles being disposed in parallel, spaced apart relation transversely of. the longitudinal direction of the opening, said nozzles being composed of individual and separable nozzle elements, said nozzle elements having solid bases secured together on the casing in c-oplanar contiguous rel-ation with the burner casing opening, said bases having 1opposing side edges and upstandin-g sides on said edges disposed transversely of the burner casing opening, the .sides of adjacent nozzle elements being in adjoining relation and having contacting end portions which lie substantially in the boundary plane between the adjacent nozzle elements and having intermediate portions between said contacting end portions which are spaced apart from each other and spaced inwardly from the Iboundary plane to form the interior gas ow open cross-section of the nozzles whereby secondary air can flow freely around the entirety of each individual nozzle with each nozzle having an individual iiame emitting therefrom and the secondary air Viiowing to each individual ame from -all sides.

2. The invention 'of claim 1, wherein said bases have Iopposing end portions clamped to the casing.

3. The invention yof claim 1, wherein said nozzle elements are stamped from sheet metal .and the adjoining sides of. adjacent nozzle elements have outer confronting faces, with the faces of the end portions of the sides disposed in sealing relation and t-he ifa-ces of the intermediate portions bein-g spaced apart.

4. The invention lof claim 3, wherein the intermediate portions of the sides are indentations which -are pressed inwardly from the main planes -of the sides.

5. The invention of :claim 4, wherein said indentations have angularly related flat faces.

`6. The invention of claim 4, wherein said indentations are `of oval cross section.

7. The invention of claim 1, where-in said nozzles have inlet ends at the bases with the interior area of the cross section of the inlet ends being less than the interior area of the cro-ss section of the upper ends of the nozzles, the upper ends constituting outlet ends and the interior cross section of the nozzles tapering smoothly upwardly from the inlet ends to the outlet ends.

8. The invention yof claim 1, wherein said nozzles have inlet ends at the bases and lupper outlet ends lfor the flow of gas with the area of cross-section of the outlet eind of each nozzle being a rnulitiple of the area of the cross section of the inlet end.

9. The invention of. claim 1, wherein an elongated wirelike member connects the Anozzle elem-ents together, said member extending parallel with the opening in the burner casing `and passing transversely through the open cross section of the nozzles where-by the nozzle elements are connected together and also .a turbulence of the gas flowing through the open cross section :of the nozzles is created,

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS France. vGreat Britain.

FREDER-{CK L. MATTESON, IR., Primary Examiner, 

1. IN A GAS BURNER COMPRISING AN ELONGATED CASING HAVING A LONGITUDINAL PRIMARY DISTRIBUTION CHAMBER, SAID CASING HAVING A LONGITUDINAL OPENING IN SAID CHAMBER; A NOZZLE PLATE ASSEMBLY STRUCTURALLY ENGAGING THE OPENING IN THE CASING AND COMPRISING A ROW OF INDIVIDUAL NOZZLES SEPARATELY UPSTANDING FROM THE CASING, SAID NOZZLES BEING DISPOSED IN PARALLEL, SPACED APART RELATION TRANSVERSELY OF THE LONGITUDINAL DIRECTION OF THE OPENING, SAID NOZZLES BEING COMPOSED OF INDIVIDUAL AND SEPARABLE NOZZLE ELEMENTS, SAID NOZZLE ELEMENTS HAVING SOLID BASES SECURED TOGETHER OIN THE CASING IN COPLANAR CONTIGUOUS RELATION WITH THE BURNER CASING OPENING, SAID BASES HAVING OPPOSING SIDE EDGES AND UPSTANDING SIDES ON SAID EDGES DISPOSED TRANSVERSELY OF THE BURNER CASING OPENING, THE SIDES OF ADJACENT NOZZLE ELEMENTS BEING IN ADJOINING RELATION AND HAVING CONTACTING END PORTIONS WHICH LIE SUBSTANTIALLY IN THE BOUNDARY PLANE BETWEEN THE ADJACENT NOZZLE ELEMENTS AND HAVING INTERMEDIATE PORTIONS BETWEEN SAID CONTACTING END PORTIONS WHICH ARE SPACED APART FROM EACH OTHER AND SPACED INWARDLY FROM THE BOUNDARY PLANE TO FORM THE INTERIOR GAS FLOW OPEN CROSS-SECTION OF THE NOZZLES WHEREBY SECONDARY AIR CAN FLOW FREELY AROUND THE ENTIRETY OF EACH INDIVIDUAL NOZZLE WITH EACH NOZZLE HAVING AN INDIVIDUAL FLAME EMITTING THEREFROM AND THE SECONDARY AIR FLOWING TO EACH INDIVIDUAL FLAME FROM ALL SIDES. 